The contracts awarded under this program support multi-disciplinary teams to identify novel B cell epitopes and elucidate mechanisms of antibody-mediated protection or pathogenesis that are important in humoral immunity in humans to emerging and re-emerging infectious diseases and potential agents of bioterrorism and their toxins. Each milestone-driven contract includes 1) epitope identification; 2) epitope validation that must include in vitro evaluation using human samples; 3) submission of epitope data, computer software, and structural data to the Immune Epitope Database and Analysis Resource; and 4) studies to help understand the mechanisms of protection or pathogenesis elicited by antibodies associated with the newly identified epitopes.